Skip to content

Instantly share code, notes, and snippets.

@dlebauer
Last active April 10, 2021 01:47
Show Gist options
  • Star 0 You must be signed in to star a gist
  • Fork 0 You must be signed in to fork a gist
  • Save dlebauer/5b147d619f35aa4edcf0e3af1e7f23b7 to your computer and use it in GitHub Desktop.
Save dlebauer/5b147d619f35aa4edcf0e3af1e7f23b7 to your computer and use it in GitHub Desktop.
how much easier is it to estimate a mean than a minimum?
n_sim <- 10000
mu <- -10
sd <- 2
n <- 30
z <- array(NA, c(3,n_sim))
for(i in 1:n_sim){
x <- rnorm(n, mu, sd)
z[1, i] <- mean(x)
z[2, i] <- min(x)
z[]
}
mean(z[1,])
mean(z[2,])
sd(z[1,])
sd(z[2,])
sd(z[1,])/mean(z[1,])
sd(z[2,])/mean(z[2,])
# "True" n-year min
qnorm(1/n, mu, sd)
# Median absolute bias (MAB)
median(abs(z[1,]-mu))
median(abs(z[2,] - qnorm(1/n, mu, sd)))
median(abs(z[2,] - qnorm(1/n, mu, sd))) / median(abs(z[1,] - mu))
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment